Fresh produce rapidly deteriorates particularly when the flesh of the fruit or vegetable is exposed, such as by peeling the or by slicing the produce. The appearance, flavor, texture, and crispness rapidly degrades. Within hours, produce, such as apples, begin to turn brown and lose their distinctive flavor. The produce loses its texture and firmness; the produce becomes soft and loses its characteristic crispness.
Many methods of preservation involve cooking, which changes flavor and texture; typically appearance is also changed. Freezing substantially preserves flavor; however, texture and crispness are affected. Furthermore, frozen foods need to be continually stored and require freezers for storage. Drying often preserves flavor, but texture, crispness and appearance are substantially affected. Refrigeration helps to preserve crispness, texture and flavor for a limited number of hours, but does not prevent browning. Chemical preservatives are often used alone or in conjunction with these methods of preserving; however, they typically leave a residual taste.
One method employs four active ingredients: an acidulant such as citric acid; a metal sequesterant or chelant, such as sodium acid polyphosphate; an enzyme inhibitor such as calcium chloride; and an antioxidant such as ascorbic acid. However, the fruit has an unpleasant taste and the produce typically turns brown within 5 days.
Citric acid, which is present in lemon juice, has been used to delay browning in fruits; however, the fruit tastes sour, becomes soft and soggy, and typically the fruit turns brown within hours.
Sodium ascorbate has also been used to preserve fruit; while the color degradation is delayed, the fruit has a noticeable taste.
Other methods often involve forming a film on the surface of the fruit; however such films often leave an unacceptable gummy feel when eaten.
It would be desirable to have a method for preserving produce, particularly cut produce, which preserves the appearance, color, texture crispness and flavor, yet does not leave an after taste nor require cooking, drying or freezing.